package com.techchat.backend.service;

import com.techchat.backend.model.User;

import java.util.List;

public interface UserService {
    void register(User user);
    User login(String username, String password);

    List<String> getAllNicknames();
    List<User> getAllUsers();                        // 【新增】

    void updateNickname(String username, String newNickname);
    void updateAvatar(String username, String avatarUrl);
}
